摘要
本实验主要对双歧杆菌22-5胞外多糖(exopolysaccharide,EPS)结构进行了研究,单糖组成及红外检测信息提示,该EPS主要含有木糖、半乳糖、葡萄糖、阿拉伯糖、鼠李糖和岩藻糖,有羧基且部分成盐,存在吡喃糖环环内醚结构;GC-MS结果显示,EPS中含有大量的D-葡萄糖和D-半乳糖,其中D-半乳糖以4位连接为主,葡萄糖多为2,3,4,6连接;高碘酸氧化和史密斯降解后产物经GC检测进一步验证,该EPS不含1→,1→6键型,可能具有1→4、1→4,6和1→2、1→2,6连接,支链中可能含有葡萄糖和半乳糖;刚果红实验证明其可能具有螺旋结构。
Bifidobacterium 22-5 from centenarians＇ faeces produces an exopolysaccharide containing Xyl, Gal, Gin, Ara, Rha and Fuc. Infrared spectroscopy revealed that it contained pyranose, possessing the carboxyl group and a certain amount of carbonoxlate, and even the cycle ether. In addition, based on GC-MS, methylation analysis, NaIO4 oxidation and Smith degradation, the primary structure was elucidated. EPS was identified as a polymer containing 4-1inked D- galactose. D- glucose partially took the form of the 2,3,4,6 connection, and 1-4 or 1-4,6 and 1-2 or 1-2,6 linkages, having neither 1-6 nor l-linkages. Besides, D- glucoses and D-galactose may be as highly branched parts of the chain. It was also showed that the EPS may have the configure of helix in the Congo red test.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2008年第4期267-271,共5页
Food Science
基金
国家"863"资助项目(2008AA10Z324)
北京市自然科学基金项目(5072025)
关键词
双歧杆菌
胞外多糖
多糖
结构
bifidobacterium
exopolysaccharide
polysaccharide
structure
